The present invention relates to aircraft, and more particularly to heavier-than-air flying craft housing a propulsion unit and a rotating airfoil. The airfoil has the effect of generating inertial stability during rotation thereof, and has a configuration which cooperates with air flow induced through the aircraft to generate lift in a direction parallel to the axis of rotation of the air-foil.
In the past, various attempts have been made to produce lift for an aircraft by providing air flow over the surface of a rotating disc or airfoil.
For example, the patent to SCHELLIN (U.S. Pat. No. 3,831,884) shows an apparatus for generating lift which includes a rotating impeller located within a cavity. Upon rotation of the impeller, air enters the cavity to drive the blade assembly 27 in rotation. The air passing over blades 31 generates a pressure differential between the top and bottom surfaces thereof thereby producing lift.
In the PHILLIPS patent (U.S. Pat. No. 3,612,445), an aircraft is disclosed wherein lift is produced by directing air over the upper surface of an airfoil in a radial direction while the airfoil rotates.
Various other examples include the MUELLER patent (U.S. Pat. No. 3,525,484), which discloses a craft 10 having a disc-shaped wing and a propeller to induce flow of air over the wing thereby creating lift; the CLOVER patent (U.S. Pat. No. 3,383,073), which discloses an aircraft having a tiltable impeller for producing lift and propulsion; the McMASTERS patent (U.S. Pat. No. 3,321,156), which discloses a tiltable engine for generating upward thrust as well as directional movement; and the HAWKINS patent (U.S. Pat. No. 3,297,278), which shows an aircraft having an impeller to direct ambient air over the top of an airfoil to produce a lifting effect.
None of these patents disclose heavier-than-air flying vehicles in which both a propulsion source, and a lift producing apparatus are located within the perimeter of the aircraft body, and in which the lift-producing apparatus takes the form of a rotating airfoil for not only cooperating with air-flow induced by the propulsion unit to flow over the lift-producing surfaces of the airfoil to generate lift, but also to provide inertial stability for the vehicle when the latter is in flight.